Gilani said in parliament he also told Brown that ‘if there were any proofs, these persons will be prosecuted under the law of Pakistan’, Gilani’s office said.

India has blamed a Pakistan-based militant group called Lashkar-e-Taiba for last month’s attacks in Mumbai, which killed more than 160 people, including three British citizens.

Pakistan has pledged full co-operation with the investigation, arrested at least two key suspects and clamped down on an Islamic charity after the UN declared it a front for terrorism.

Brown said co-operation among investigators was vital to defeat transnational terrorism and said three-quarters of the most serious terrorist plots investigated in Britain had links to al Qaida in Pakistan.

Brown also asked India to let British police question the only gunman captured alive during the Mumbai attacks. India has made no public response.

The attacks heightened tension between India and Pakistan, nuclear-armed neighbours who have already fought three wars, and added to the strain on the pro-Western government in Islamabad.

Islamist parties and nationalist commentators have criticised the government for moving against the charity, Jamaat-ud-Dawa, under US and Indian pressure.

Gilani told governors the charity’s extensive welfare activities, which includes running schools and clinics, would continue under government oversight and different names. He said Pakistan had tried hard to lower the tension, but reiterated it was ready for war “if it is thrust on us”.